MCS published updated heat pump standards on 10 December 2025, the first step in implementing air-to-air heat pumps across its installer and product Schemes1. MCS states that the updates "more explicitly cover the requirements of air-to-air heat pump products and installations"1. The standards body says there are more steps to be taken before air-to-air heat pumps are fully implemented into MCS1.
The published documents include MCS 007 V8.0, the Heat Pump Product Standard, and MIS 3005-D V3.0, the Heat Pump Design Standard, in the Current Scheme, alongside MIS 3005-D: 2025 V2.0, MCS 031 a): 2025 V2.0 and MCS 031 b): 2025 V1.0 in the Redeveloped Installer Scheme1. MCS 031 has been separated into two parts: 031 a) covers hydronic heat pumps and 031 b) covers air-to-air heat pumps, with a new methodology and tool1.
Changes to MCS 007 include a new requirement that the Seasonal Coefficient of Performance data needed to raise a certificate must be taken from the ErP label1. MCS later reported new requirements for minimum energy efficiency, maximum sound power level and water heating energy efficiency for air-to-air heat pump systems, and updated test conditions suitable for air-to-air heat pumps2. A new section was added to clause 5.5.3 in the Current Scheme and to clause 3.4.3 in the Redeveloped Installer Scheme covering system design of air-to-air heat pumps1.
On installer competence, MCS states that a business's Technical Supervisor assigned to an air-to-air heat pump installation must hold competence in Refrigeration, Air Conditioning and Heat Pumps (RACHP) at Level 3 or above2. MCS says RAC level 3 S/NVQ qualifications are recognised UK-wide and by all industry organisations in the refrigeration and air conditioning sector as a suitable level of competence2. It adds that some existing MCS installation businesses may already hold these qualifications within their team, while others will need to bring the competencies in through training, hiring or subcontracting2.
"MCS has updated the relevant heat pump standards to more explicitly cover the requirements of air-to-air heat pump products and installations."
Why it matters for households
Air-to-air heat pumps provide cooling as well as heating, and MCS states they can be more accessible for households living in flats or smaller homes where central heating retrofits can be challenging2. MCS also states they will soon be eligible for funding under the Boiler Upgrade Scheme2. Until certification bodies hold the appropriate UKAS accreditation and can assess and certify air-to-air products and installations, MCS certified installation of these systems is not yet available1. For a household, that means the route to a certified air-to-air installation, and to any grant funding attached to it, depends on progress that has not yet been completed. The competence requirement also means the technical supervisor signing off an installation must hold a Level 3 RACHP qualification, a different skill set from that used on water-based systems2. MCS says the distinction between air-to-water and air-to-air systems has been made clear in MIS 3005-D and MIS 3005-I2.
What happens next
MCS says it is working with installer certification bodies to support them through gaining UKAS accreditation to offer air-to-air heat pump certification, with timescales varying depending on certification body preparation, readiness and UKAS resources2. It is also working with product certification bodies to ensure a pipeline of air-to-air heat pump products is available in the MCS Product Directory and ready for use in MCS certified installations2. Core redeveloped Scheme documents, including the Installer Operating Requirements and Conformity Assessment Guidelines, have been updated and MCS states they will be available to view on its website in the coming weeks2. No dates for full implementation have been reported.
Sources2 cited
- Heat Pump Standards Update: Implementing Air-to-Air into MCS - MCS, mcscertified.com
- Update on the implementation of air-to-air heat pumps into MCS - MCS, mcscertified.com